1. Field of the Invention
This invention relates to a floating nuclear power reactor and more particularly to a floating nuclear power reactor wherein the containment structure of the reactor is self-cooling. This invention relates even more particularly to an emergency heat exchange system for the nuclear power reactor.
2. Description of the Related Art
In most nuclear power reactors, a primary electrically operated water pump supplies cooling water to the reactor. In many cases, a secondary or back-up water pump is provided in case the primary water pump becomes inoperative. However, should the electrical power source for the water pump or water pumps be disrupted such as in a tsunami, a typhoon or an earthquake, the water pumps are not able to pump cooling water to the reactor which may result in a dangerous meltdown. Further, in some situations, the pipes supplying cooling water to the reactor may fail due to natural causes or a terrorist attack.
Currently, there are land based reactor cooling systems available which store water in a tank above the level of the reactor which will passively feed the reactor in case of pump or electricity failure. These tanks are designed to have enough water to cool the system for three days until help can arrive and more water can be pumped in from outside. The problem is that water stored in these tanks is of finite quantity. The tanks will work in case of an emergency shut down like in Fukushima, Japan, but will not work in the case of a pipe breakdown leaking a huge amount of water to the exterior. The reactor core will heat the water supplied from the tank and steam will escape via the pipe breakdown and the water will run out. Once the water runs out, the reactor core will melt due to overheating and explode. It is therefore necessary to be able to supply an infinite amount of water to compensate for lost water via a leaking pipe.
Further, current day reactors are protected by huge containment structures but this is not the answer to pipe breakdown outside or inside the containment chambers. A terrorist attack on the turbine room outside the containment structure is probably more dangerous than an attack on the containment structure since such an attack would result in multiple pipes breaking down, thereby breaking the water circuit between the reactor, turbine and condenser. Such an attack could also result in a breakdown of electrical control systems. This would result in the loss of circulating water to the reactor with the emergency stored water being unable to compensate for all the leaking pipes. In such a situation, the reactor will overheat without heat removal and explode.
The invention of the co-pending parent application represents a major improvement in the art. The instant invention represents a further improvement in the art.